It was supposed to be "the war that will end war" - according to the  misplaced optimism of British author H.G. Wells, and countless others like him  who cheerfully expected "our boys" to be home by Christmas 1914.   Involving all  the world's great powers, more than 70 million combatants, and over 9 million  fatalities, it became one of the largest wars in history.

And perhaps most tragically, those who died in the trenches, or on the shores  of Gallipoli, had no inkling of the underlying causes, quarrels and agendas for  which they were to sacrifice their lives.  While its origins are still hotly  debated by historians, this is no mere academic discussion.  As you'll hear in  tonight's totally engrossing show, the legacy of the Great War is still very  much with us today - setting the agenda for many of the current events in the  Middle East and beyond.

Our special guest is acclaimed historian Professor Sean McMeekin,  whose radical and assiduous scholarship has shed much new light on this  much-misunderstood conflict. Sean's books include The  Berlin-Baghdad Express: The Ottoman Empire and Germany's Bid for World  Power,  The  Russian Origins of the First World War,  and the forthcoming July  1914: Countdown to War.